User manual

9 Functions and operations in the position control mode
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9.5 Absolute system
Install the optional battery BAT01A (sold separately). When the battery is connected, the current position will
be retained even in the event of power outage or after the driver power is cut off.
Set the absolute system function using the absolute system setting switch (SW1-3).
ON: Enable the absolute function
OFF: Disable the absolute function (factory setting)
Note
• If an absolute position loss alarm generates when the absolute function is enabled, the
following causes are suspected. Reset the alarm by referring to “Resetting the absolute
position loss alarm” on p.63.
· The power was turned on for the first time after connecting the battery.
· The battery was disconnected while the main power supply and 24 VDC power supply
were cut off.
· The battery voltage became low while the main power supply and 24 VDC power
supply were cut off.
· The encoder cable was disconnected.
· The coordinate control range was exceeded. (In this condition, a position range error is
output first. When the motor is operated again, an absolute position loss alarm will
generate.)
• If the absolute function is set to “Enable” but no battery is connected, a “no battery”
alarm will generate.
• If a battery is connected when the absolute function is set to “Disable,” an “ABS not
supported” alarm will generate.
• The new setting of the absolute system setting switch will become effective after the
power is cycled. If a 24 VDC power supply is used, also cycle the 24 VDC power
supply.
• The factory setting of the absolute function is “OFF” (Disable). Accordingly, position
information will be lost once the power is turned off.
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Coordinate control range
The range of motor positions that can be controlled using the absolute system function corresponds to the
smaller of the two ranges specified below. Which range is used varies depending on the motor resolution:
• Current position : −2,147,483,648 to +2,147,483,647 pulses
• Amount of rotation : −32,768 to +32,767 revolutions
Note
When the current position exceeds the coordinate control range, a position range error
alarm will generate. Resetting the position range error alarm will cause an absolute
position loss alarm to generate.
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Loss of absolute position
If, when the absolute function is enabled, the position information stored in the driver is lost due to low
battery voltage, etc., an absolute position loss alarm will generate. Reset the alarm by referring to “Resetting
the absolute position loss alarm” on p.63.
You can set how to enable pulse input after an absolute position loss alarm has been reset. Set the method in
the system parameter for operation after absolute position loss alarm reset [SyS-1-01].
Parameter for operation after
absolute position loss alarm reset
[SyS-1-01]
Description
Enable pulse input at the ON edge
of the P-REQ input (initial value)
Even after resetting the alarm with the ALM-RST input, pulse
input will remain disabled until the P-REQ input is turned ON. If a
pulse is input before the P-REQ input turns ON, an absolute
position loss alarm will generate again.
Enable pulse input Pulse input will be enabled once the alarm is reset with the
ALM-RST input.
Note
When a system parameter has been changed, the new parameter will become effective
after the power is cycled. If a 24 VDC power supply is used, also cycle the 24 VDC power
supply.